Radio frequency identification (RFID) systems are used for a variety of different applications. As one example, RFID systems are commonly used to track and monitor shipping containers or other mobile assets. RFID tags are attached to containers or other assets, and can exchange wireless communications with other system components, including interrogators and/or readers. In systems of this type, it can be beneficial to determine in real time the current status of any given tag, including its location, speed and direction of movement. Systems of this type are sometimes referred to as real-time locating systems (RTLS). Although existing techniques for collecting real-time information in RFID systems have been generally adequate for their intended purposes, they have not been entirely satisfactory in all respects.